1. Field of the Invention
The present invention relates to mobile station equipment that is carried on a mobile unit or in a mobile vehicle or carried by a subscriber to offer communications services to the subscriber. The invention also relates to base station equipment for forming a wireless zone in a region where a mobile station can be positioned and providing channel control in the wireless zone. Furthermore, the invention relates to an exchange that associates with this base station equipment and performs call processing. In addition, the invention relates to a mobile communication system composed of such mobile station equipment, base station equipment, and exchange.
2. Description of the Related Art
In recent years, mobile communication systems have become rapidly widespread because of competition among communication service providers and liberalization of the market. Therefore, subscribers receive various kinds of communication services through in-vehicle terminals, as well as through transportable terminals.
FIG. 14 illustrates an example of configuration of a mobile communication system.
In this figure, mobile station equipment 80 is located within a wireless zone 82 formed by radio base station equipment 81, which is connected with radio control station equipment 83 through a communication link 81L. An exchange 84 connected with switching networks and home location registers (none of which are shown) is connected with the radio control station equipment 83 through a communication link 84L.
The mobile station equipment 80 comprises: antennas 85M-1, 85M-2; a TX/RX part 86M connected with the loading points of these antennas; a processor 87M having input/output ports connected with the control terminals of the TX/RX part 86M and with the output of a speedometer (not shown); a microphone 88 and a receiver 89 both connected with the modulation input and demodulation output, respectively, of the TX/RX part 86M; and a operation/indication part 90 connected with given input/output ports of the processor (CPU) 87M.
The radio base station equipment 81 comprises: an antenna 85B; a TX/RX part 86B connected with the loading point of the antenna 85B; a transmission path interfacing part 91B connected with the modulation/demodulation terminal of the TX/RX part 86B and with one end of the communication link 81L described above; and a processor (CPU) 87B, whose input and output ports of the processor 87B are connected with the control terminals of the TX/RX part 86B and of the transmission path interfacing part 91B.
The radio control station equipment 83 comprises a transmission path interfacing part 91C and an exchange interfacing part 92 both cascaded between the other end of the communication link 81L and one end of the communication link 84L, and a processor (CPU) 87C whose input and output ports are connected with the control terminals of the transmission path interfacing part 91C and of the exchange interfacing part 92.
The exchange 84 comprises: a radio interfacing part (RI) 93 directly connected with the other end of the transmission path 84L; a switch 94 having ports connected with the radio interfacing part 93 and the aforementioned switching networks, respectively; and a processor (CPU) 87E having communication ports connected with the aforementioned radio interfacing part 93, the switch 94, and home location register, respectively.
In the mobile communication system of the construction described so far, the TX/RX part 86B incorporated in the radio base station equipment 81 forms the wireless zone 82 under control of the processor 87B and interfaces, through the transmission path interfacing part 91B, with the communication link 81L and the radio channel both forming the wireless zone 82.
In the radio control station equipment 83, the processor 87C cooperates with the processor 87B disposed opposite to the processor 87C through the transmission path interfacing part 91C, the communication link 81L, and the transmission path interfacing part 91B, and performs channel control of the wireless zone (radio channels).
The transmission path interfacing part 91C and the exchange interfacing part 92 interface the communication links 81L and 84L with each other, based on the procedure of the channel control performed by the processor 87C in this way.
In the exchange 84, the processor 87E performs, by associating with the processor 87C that is located opposite to the processor 87E through the radio interfacing part 93, the communication link 84L, and the exchange interfacing part 92, call processing of the following termination call, terminating from the switching networks to the mobile station equipment 80 and the originating calls of the mobile station equipment 80 that are identified by the radio interfacing part 93.
The call processing adapts to the aforementioned channel control. The originating calls may contain calls for location updating. This call processing contains setting and resetting of a speech path to the switch 94.
In the mobile station equipment 80, when a origination request a call containing a phone number is given by the operation/indication part 90, for example, the processor 87M transmits an origination call signal to a certain radio channel formed by the radio base station equipment 81, and performs the channel control by associating associates with the processor 87B incorporated in the radio base station equipment 81 and with the processor 87C incorporated in the radio control station equipment 83.
When the corresponding origination call is completed based on the procedure of the channel control, the TX/RX part 86M secures a full duplex communication path between the mobile station equipment 80 and the radio base station equipment 81 by matching the speech signal to be sent and received through the microphone 88 and the receiver 89 to the radio channel assigned by the processor 87C incorporated in the radio control station equipment 83 over the period during which the completed call persists.
The processor 87M obtains the speed of the local station given by the speedometer described above and judges whether this speed is greater or smaller than a given upper limit.
The processor 87B recognizes the period for which the speed exceeds the upper limit. During this period, the processor 87B refrains from performing processing that should be invoked as the aforementioned channel control in response to an origination request given by the operation/indication part 90 and/or a paging signal that is sent by the radio base station equipment 81 and addressed to the local station through the antennas 85M-1, 85M-2, and TX/RX part 86M. At the same time, the processor 87B refrains from performing processing associated with location updating that should be invoked based on the procedure of the channel control.
In particular, as long as the upper limit described above is predetermined to a preferable value while the mobile unit or vehicle carrying the mobile station equipment 80 is moving at a high speed, origination calls and response to terminating calls for which the operation/indication part 90 is operated in some manner are restricted. Furthermore, location updating that is a factor of the transition to a state in which a subscriber can perform such operations are permitted is prolonged.
Accordingly, accidents that would normally be caused by user""s operation on the mobile station equipment 80 while the mobile station equipment 80 is moving at a high speed are prevented with high reliability.
The TX/RX part 86M monitors the field strength level of receiving waves that reached the antennas 85M-1, 85M-2 from the antenna 85B incorporated in the radio base station equipment 81. The TX/RX part 86M appropriately selects the receiving waves of greater field strength level from those receiving waves and thus maintains high the speech quality according to switching diversity. The receiving waves are not restricted to waves that reach the antennas 85M-1, 85M-2 through the radio channel used for speech.
In the conventional configuration described above, the output of the speedometer described above is connected with the corresponding input port of the processor 87M through a dedicated connector and so there is the possibility that the connector is intentionally removed by the driver or that the driver forgets reattaching the connector after once removed.
In particular, the mobile unit or vehicle carrying the mobile station equipment 80 is able to run at a high speed without attaching the connector and, therefore, prevention of the aforementioned accidents cannot be accomplished reliably due to lack of driver""s safety mind or human errors.
Such inappropriate removal of the connector can be prevented certainly by incorporating dedicated hardware in the mobile station equipment 80 to measure the moving speed of the moving unit or vehicle instead of the speedometer and to inform the processor 87M of the moving speed.
However, this configuration lowers of the cost effectiveness of the mobile station equipment and increases the cost. Although this configuration may be applied to newly manufactured mobile station equipment, it is impossible to apply it to already operating mobile station equipment or to those kinds of mobile station equipment which are not operated but appear on the market.
Consequently, it has not been assured that the aforementioned accidents are prevented.
It is an object of the present invention to provide mobile station equipment, base station equipment, exchange, and mobile communication system that can prevent the aforementioned accidents economically and reliably without modifying the standard hardware structure.
It is another object of the invention to provide technologies for efficiently and reliably preventing accidents which would normally be caused by some operation by a human operator in response to a call occurring while the unit or vehicle is moving at a high speed.
It is a further object of the invention to prevent the aforementioned accidents, according to the procedure of the channel control provided by a base station or the call processing performed by an exchange associated with this base station.
It is a yet other object of the invention to provide technologies that enable speed obtained by mobile station equipment according to the invention to be effectively utilized by a base station or an exchange.
It is a still other object of the invention to provide technologies for adapting to the form of channel control or call processing flexibly and reliably.
It is an additional object of the invention to provide technologies for distributing functions or load in a desired manner between a base station and an exchange performing call processing associating-with the base station.
It is a yet further object of the invention to provide technologies for flexibly adapting to the procedure of the channel control provided by a mobile station or the call processing performed by an exchange, as well as the speed of the mobile station.
It is a yet additional object of the invention to provide technologies for preventing the aforementioned accidents reliably while flexibly matching the form of channel control or call processing.
It is a still additional object of the invention to provide technologies for distributing either or both of the functions and/or the load between a mobile station and an exchange.
It is a further object of the invention to provide technologies for improving the quality of services offered to a mobile station and maintaining the quality high.
It is a further object of the invention to provide technologies for flexibly adapting to the specifications and structure of a mobile communication system without substantially increasing the cost and for enhancing the safety of the subscriber, as well as the quality of services.
The objects described above are achieved by mobile station equipment, base station equipment, and exchange which comprise some or all of sections for monitoring the speed of a mobile station, section for judging whether or not the speed exceeds a predetermined threshold value, and section for restricting either or both of channel control and call setting for a call occurring at the corresponding mobile station when the result of the judgement is true. These mobile station equipment, base station equipment, and exchange operate alone or are associated with each other through radio transmission paths or other links.
In these mobile station equipment, base station equipment, and exchange, accidents which would normally be caused by some operation of a human operator in response to a call that occurred while the mobile station is moving at a high speed are prevented efficiently and reliably.
The aforementioned objects are achieved by mobile station equipment characterized in that the speed of the local station is obtained based on a change in an attribute of receiving waves reached from a radio base station.
In this mobile station equipment, the speed of the mobile station equipment is obtained according to the receiving wave that reached the local station from the base station and so the size of the hardware is reduced greatly compared with the case where a dedicated section for obtaining the speed is provided.
The aforementioned objects are also achieved by mobile station equipment characterized in that a navigational system is installed and that the speed of the local station is obtained as a rate of change in the location of the local station given by the navigational system.
In this mobile station equipment, the speed of the mobile station equipment is obtained as long as the speed monitoring section operates normally according to the aforementioned radio navigation or self-contained navigation, even if the quality of receiving waves that reached the local station from a radio base station is quite poor.
Accordingly, the state in which the channel control should be aborted because the mobile station equipment is moving at a high speed is recognized with high accuracy.
The aforementioned objects are also achieved by base station equipment characterized in that the speed of a mobile station is obtained according to a change in an attribute of receiving waves coming from the mobile station.
In this base station equipment, the speeds of individual mobile stations are obtained according to waves received from these mobile stations and, therefore, the size of hardware is greatly reduced compared with the case where dedicated sections for obtaining the speeds are provided.
The aforementioned objects are also achieved by an exchange characterized in that the speed of a mobile station is obtained according to the frequency at which the transmission quality of a baseband signal obtained by demodulating receiving waves reaching the local station from the mobile station deteriorates.
In this exchange, the speeds of individual mobile stations are obtained according to each received wave that reached the local station from each mobile station and, therefore, the size of the hardware is reduced greatly compared with the case where dedicated sections for obtaining the speeds are provided.
The aforementioned objects are also achieved by a mobile station equipment, a base station equipment, and an exchange characterized in that they perform man-machine interfacing that is involved in the notification that said restriction is to be made.
In these mobile station equipment, base station equipment, and exchange, the operator can recognize that the reason why some of the origination, termination, and location updating are restricted or why the conversation is forced to be aborted is because of the high-speed movement of the local station. Alternatively, the operator can recognize the existence of a mobile station for which conversation is aborted as described above.
The aforementioned objects are also achieved by an exchange characterized in that calls to be restricted are judged according to either or both of originating class and/or termination class.
In this exchange, call processing is aborted irrespective of the service class of originating party or terminating party and so restriction of originating or termination calls and compulsory clearing of these calls are avoided.
The aforementioned objects are also achieved by mobile station equipment, base station equipment, and exchange characterized in that information necessary for retrial or continuation of channel control or call setting for the restricted calls is kept by them and that the retrial is automatically performed when they are in a state in which the restriction should be canceled.
In these mobile station equipment, base station equipment, and exchange, originating party and terminating party of the restricted calls that are restricted due to the high-speed of a mobile station equipment that is an originating party or terminating party can easily converse without having cumbersome operations associated with re-origination or callback when the speed is below the upper limit.
The aforementioned objects are also achieved by a mobile station equipment, a base station equipment, and an exchange characterized in that channel control or call setting necessary to compulsorily abort the corresponding completed call is performed when the speed of the mobile station exceeds the predetermined upper limit while the completed call exists.
In the mobile station equipment, base station equipment, and exchange, conversation with a mobile station at a speed exceeding the upper limit is quickly interrupted and so accidents due to the high speed of the vehicle can be prevented precisely.
The aforementioned objects are also achieved by a base station equipment that is a combination of base station control equipment and radio base station equipment, wherein the base station control equipment is a main component providing channel control, and the radio base station equipment interfaces with this base station equipment and a radio transmission path.
In this base station equipment, it is possible to flexibly adapt itself to a zone configuration or channel allocation, as well as to an area in which mobile stations can be located and to the distribution of these mobile stations in this area. Consequently, the service quality is improved and maintained high.
The aforementioned objects are also achieved by a mobile communication system that is a combination of the aforementioned mobile station equipment, base station equipment, and exchange.
In this mobile communication system, when any call occurs in the mobile station equipment, accidents which would normally be caused when the speed of the mobile station equipment exceeds a predetermined upper limit can be prevented reliably by association of the mobile station equipment with the aforementioned radio base station equipment, radio control station equipment, and exchange.
The nature, principle, and utility of the invention will become apparent from the following detailed description when read in conjunction with the accompanying drawings in which like parts are designated by identical reference numbers